Single chain variable fragment (scfv) elongation mutants

Abstract

The present invention relates to the provision of single chain variable fragment (scFv) elongation mutants. In addition, the present invention relates to a pharmaceutical composition comprising said scFv elongation mutants, as well as a nucleotide sequence encoding said scFv elongation mutants, a vector comprising said nucleotide sequence or a host cell expressing said nucleotide sequence. Particular embodiments relate to elongation mutants of the scFv-h3D6 which is derived from monoclonal antibody mAb-h3D6 (bapineuzumab). It is further disclosed a method of prevention or treatment of a patient in risk of suffering, or already diagnosted as suffering, Alzheimer disease that comprises the administration to said patient of an effective amount of the scFv elongation mutants of scFv-h3D6.

1 . An isolated single chain variable fragment (scFv) comprising variable regions of the heavy (V H ) and light chains (V L ) of a monoclonal antibody, particularly a human or humanized monoclonal antibody, characterized in that the C-terminal end of said light chain is elongated by:
 i) an amino acid residue, or   ii) a polypeptide having at least 2 amino acid residues.   
     
     
         2 . An isolated single chain variable fragment according to  claim 1  comprising variable regions of the heavy (V H ) and light chains (V L ) of humanized monoclonal antibody mAb-h3D6, characterized in that the C-terminal end of said light chain is elongated by:
 i) an amino acid residue, or 
 ii) a polypeptide having at least 2 amino acid residues 
 
     
     
         3 . An isolated single chain variable fragment according to  claim 2  wherein the single chain variable fragment aggregates with the Aβ 1-42  peptide to form worm-like fibrils. 
     
     
         4 . The single chain variable fragment according to  claim 1 , wherein the C-terminal end corresponds to lysine residue 107 of the light chain (V L -K107) of the wild-type mAb-h3D6 using the Kabat Numbering Scheme. 
     
     
         5 . The single chain variable fragment according to  claim 1 , wherein the C-terminal end of said single chain variable fragment is elongated by a glycine residue, a lysine residue, a threonine residue, a serine residue or an arginine residue. 
     
     
         6 . The single chain variable fragment according to  claim 1 , wherein the C-terminal end of said single chain variable fragment is elongated by an arginine-threonine dipeptide. 
     
     
         7 . The single chain variable fragment according to  claim 5  represented by SEQ.ID.NO: 2 or SEQ. ID. NO: 3. 
     
     
         8 . The single chain variable fragment according to  claim 6  represented by SEQ.ID.NO: 4. 
     
     
         9 . A nucleotide sequence encoding the single chain variable fragment according to  claim 1 . 
     
     
         10 . A vector comprising the nucleotide sequence according to  claim 9 . 
     
     
         11 . A host cell expressing the nucleotide sequence according to  claim 9 . 
     
     
         12 . An isolated single chain variable fragment according to  claim 1  for use as medicament. 
     
     
         13 . An isolated single chain variable fragment according to  claim 1  for use in the prevention and/or treatment of Alzheimer's disease in a patient. 
     
     
         14 . Use of an isolated single chain variable fragment according to  claim 1  in the manufacture of a medicament for the prevention and/or treatment of Alzheimer's disease. 
     
     
         15 . A pharmaceutical composition comprising at least an isolated single chain variable fragment according to  claim 1 , and, optionally, at least a second active ingredient and/or at least an inert ingredient such an excipient and/or carrier. 
     
     
         16 . A method of prevention or treatment of a patient in risk of suffering, or already diagnosed as suffering, Alzheimer disease that comprises the administration to said patient of an effective amount of the scFv elongation mutants of  claim 1 . 
     
     
         17 . A method of prevention or treatment of a patient in risk of suffering, or already diagnosed as suffering, Alzheimer disease that comprises the administration to said patient of an effective amount of the scFv elongation mutants of the pharmaceutical composition of  claim 15  comprising the same.